This Application claims priority of China Patent Application No. CN 201310409769.4, filed on Sep. 9, 2013, and the entirety of which is incorporated by reference herein.
Field of the Invention
The present invention generally relates to display device. More particularly, the present invention relates to an organic light-emitting diode (OLED) display and fabrication method thereof.
Description of the Prior Art
Organic light emitting diode display (OLED display) has long been considered to be the most competitive one of the next generation display technologies, with the advantages including self-luminous without needing a backlight module, faster response, and lower operating voltage.
A general OLED display has self-emission characteristics and uses an organic material layer composed of an organic material. When a current is applied and the current passes through the organic material layer, the organic material in the organic material layer emits light. With different organic materials, OLED display can emit light of different colors to achieve multi-color or full color displays.
Currently, the organic material layer of an OLED display can be formed by vapor depositing red (R), green (G), blue (B) color organic material layer with a vapor deposition apparatus. The vapor deposition apparatus has a mask with a plurality of openings corresponding to a plurality of pixel regions on the organic material layer. In the vapor deposition process, the organic material of one specific color of the three primary colors R, G, B, for example red color (R), is vapor deposited onto the pre-selected pixel region through the openings of the mask. Thereafter, the mask is shifted to another pixel region, and the vapor deposition process is repeated to sequentially form the rest colors (G, B) of the organic materials through the openings of the mask.
However, during the vapor deposition process, residual organic material remains near the openings of the mask. The residual organic material has a weight, and over time, the weight of the residual organic material deforms the mask and changes the shape of the openings, resulting in insufficient mask alignment accuracy, which leads to mixed color regions in the organic material layer and color shift problems.